Report details how global warming may affect Mass.

Wednesday

Sep 28, 2011 at 3:15 AM

JAY LINDSAY,Associated Press

BOSTON (AP) — A state-mandated report on global warming and Massachusetts, released Tuesday, predicts more ice storms and droughts and endangered coastal development in the decades to come, but also details ways the state can prevent or adapt to predicted changes.

The Massachusetts Climate Change Adaptation Report was required under a 2008 law aimed at sharply curbing the state's greenhouse gas emissions, a major factor in global warming. The law requires the state to make an 80 percent reduction in total emissions by 2050, compared to 1990 levels.

The 129-page report sums up how rising temperatures would hit various sectors, including the ecology, business and local infrastructure. A 34-member advisory committee of scientists, environmentalists, local and regional planners, and medical and business groups helped prepare the report.

Steve Long, director of government relations for The Nature Conservancy, which pushed to make the assessment a mandatory part of the law, said he sees the report as a "blueprint," containing basic principles and steps for policymakers to use to deal with unwanted effects of global warming.

"Climate change impacts are going to affect every facet of our lives," Long said. "We need to be smart about the way we go about living our lives."

Among the new realities Massachusetts could face by 2100 are far more 100 degree days annually, less snow, and warmer, rising coastal waters. The report notes various local climate and weather trends, including an average temperature increase of half a degree per decade in the Northeast since the 1970s and a 5 to 10 percent increase in total precipitation in the region since 1818 — with more of this precipitation now falling as rain.

Other predictions about changes in Massachusetts by 2100 included a high and low range to cover uncertainties about future levels of greenhouse gas emissions. Among them are:

— Temperatures an average of five to 10 degrees higher.

— Three to 28 more days annually of temperatures 100 degrees or higher.

— 29 to 43 more days in the growing season.

— A rise in sea level from 11 to 79 inches.

The consequences of such changes would be wide-ranging, from altered bird and fish migrations to endangering the development in coastal towns, according to the report.

A map included in the report shows key Boston infrastructure and landmarks that were not previously threatened in a 100-year flood, such as Quincy Market and the TD Banknorth Garden, would be surrounded by water in such a flood.

And rainy, icy winters would increase the number of damaging ice storms, while less snow would mean less skiing and deal a blow of several hundred million dollars to the local economy, the report says.

The projections aren't universally grim: A longer growing season could mean greater crop yields, with more varieties, as well as extended spring and summer tourist seasons, the report says.

"Societies across the world have a long record of adapting and reducing their vulnerability to the impacts of weather- and climate-related events such as floods, droughts and storms," the report read. "Nevertheless, additional adaptation measures will be required ... to reduce the adverse impacts of projected climate change and variability."

The report says planners should work with utilities to make sure they have the land needed to build energy infrastructure away from parcels that might be threatened by rising sea levels or more frequent floods.

To combat more frequent droughts, the report suggests improving water storage and recycling. It also suggests reducing the number of vulnerable coastal properties by having the government buy them when possible, or through new conservation restrictions.